Wheat is a cereal grain and one of the most widely cultivated and important staple crops in the world. It belongs to the Triticum genus and the most common species of wheat is Triticum aestivum, also known as common wheat or bread wheat. Wheat is grown in diverse climates and regions globally, making it a crucial crop for food production and agricultural economies.
Wheat is primarily cultivated for its edible seeds, known as wheat berries or kernels. These kernels are milled to produce flour, which is then used to make various food products such as bread, pasta, pastries, cakes, and breakfast cereals. The versatility of wheat and its ability to be processed into different forms makes it a fundamental ingredient in numerous cuisines worldwide.
According to the Food and Agriculture Organization of the United Nations (FAO), the total area sown with wheat worldwide was estimated to be around 220 million hectares (approximately 543 million acres).
The largest wheat-producing countries, accounting for a significant portion of the global wheat area sown, include China, India, Russia, the United States, Canada, and Australia.
Wheat is the major cereal crop of Pakistan and the largest area under cultivation in Pakistan and plays a significant role in the economic stability of the country. It was grown on 8976 thousand hectares last year with a production of 26394 thousand metric tons.
Botany of Wheat
- The scientific name of wheat is Triticumaestivum, belonging to the Poaceae family.
- The inflorescence of wheat is spiked.
Types of Roots
Wheat has two root system
- Primary roots(Seminal roots)
Seminal roots are the first roots to emerge from the germinating wheat seed. They develop from the radicle, which is the embryonic root present in the seed. Seminal roots provide initial anchorage and absorb water and nutrients from the soil. These roots are relatively short-lived and serve as the foundation for the development of the crown root system
- Secondary roots (Crown roots)
Crown roots develop from the base of the stem, near the soil surface. They are known as secondary or nodal roots because they originate from the nodes of the stem. Crown roots are more extensive and longer-lived than seminal roots. They play a crucial role in water and nutrient uptake, providing a substantial portion of the plant’s root system.
The combination of seminal roots and crown roots forms the root system of a wheat plant. The crown root system is responsible for the majority of water and nutrient absorption and provides stability to the plant. It spreads horizontally and vertically in the soil, adapting to the available resources and environmental conditions.
Characteristics of wheat:
Wheat is a monocotyledonous plant, belonging to the monocot group of flowering plants. Monocots are characterized by having a single seed leaf (cotyledon) when they germinate.
- C3 Pathway
Wheat follows the C3 photosynthetic pathway, which means it utilizes the C3 carbon fixation process during photosynthesis. This pathway is less efficient in terms of water usage compared to the C4 pathway followed by some other plants.
- Long-day winter crop
Wheat is categorized as a long-day winter crop. It requires a longer duration of daylight to initiate flowering and complete its life cycle. It is typically sown in the fall or winter and harvested in the spring or summer, depending on the variety and growing region.
Wheat is primarily a self-pollinating crop. It has both male and female reproductive structures in the same flower, allowing for self-fertilization. However, cross-pollination can also occur to some extent through wind or insect activity.
Types of wheat
- Common/Bread Wheat (Triticum aestivum):
Common wheat, also known as bread wheat, is the most widely cultivated and consumed type of wheat. It has a high gluten content, which gives it excellent baking properties and makes it suitable for bread-making.
- Durum Wheat (Triticum durum):
Durum wheat is known for its hard texture and high protein content. It is primarily used for making pasta, couscous, and semolina flour. Durum wheat kernels are larger and harder compared to common wheat.
- Spelt Wheat (Triticum spelta):
Spelt wheat is an ancient variety of wheat that has gained popularity in recent years due to its nutty flavour and potential health benefits. It has a tougher husk and is often considered a more primitive form of wheat.
- Khorasan Wheat (Triticum turgidum ssp. turanicum):
Khorasan wheat, commonly known by its trademarked name Kamut, is an ancient grain with origins in the Middle East. It has larger kernels than common wheat and is known for its rich, buttery flavour. Kamut is often used in baking and is considered an alternative to modern wheat varieties.
- Emmer Wheat (Triticum dicoccon):
Emmer wheat is one of the oldest cultivated grains and is believed to be the ancestor of modern wheat. It has a husk that tightly encloses the grain, making it more challenging to process. Emmer wheat is used in traditional foods such as farro and is often favoured for its nutty taste.
Growth Stages of Wheat
Germination/Emergence: This stage begins when the seed absorbs water and starts to sprout. The shoot emerges from the seed, and the primary roots begin to develop.
Tillering: During tillering, the wheat plant produces additional shoots, known as tillers, from the base of the main stem. These tillers contribute to the overall plant density and potential grain yield.
- Stem elongation
Stem Elongation: Stem elongation is characterized by the rapid growth of the main stem and tillers. The plant height increases significantly during this stage.
Booting: In the booting stage, the head (inflorescence) is enclosed within the flag leaf sheath. The head continues to develop and differentiate within the protective sheath.
Heading/Flowering: Heading refers to the emergence of the head from the flag leaf sheath. It is the beginning of the flowering stage when the wheat plant produces flowers. Cross-pollination may occur during this period.
- Milking stage
Milking Stage: The milking stage is marked by the appearance of milky fluid in the developing kernels. The kernels are still soft and contain a high moisture content.
- Dough stage
Dough Stage: During the dough stage, the developing kernels begin to harden. The transition from a milky consistency to a firm and starchy texture. This stage is important for determining the maturity and readiness for harvest.
Maturity: The maturity stage is when the wheat crop is fully ripe and ready for harvest. The kernels have reached their maximum size and have turned golden or brown in colour. The crop is harvested at this stage to ensure optimal grain quality and yield.
Wheat Production Technology
Wheat sowing Time
- 1st Nov to 20th Nov is the best time for sowing in irrigated areas but can be sown till 30th Nov.
- 20th Oct to 20th Nov is the best time for sowing in the barani areas
- Sow Fakhri Bhakhar from 25th Oct to 15 Nov
- Sow Bhakhar starts from 10th Nov to 10th Dec.
- Anjan-17, Zincol-16, Johar-16, Borlaug-16, Ujala-16, Faisalabad-8 can be sown till 10th Dec.
- Late sowing till January but can reduce the yield up to 50%
Land Preparation for Wheat
- After harvesting of previous crop applied pre-soaking irrigation
- At wattar condition, 3-4 ploughings with 3 plantings are done for the removal of all the germinated weeds
- For seedbed preparation in loamy soils, 2 ploughing with successive planking is done and in sandy soil, only one ploughing with planking is practised
- For zero tillage sowing no prior land preparation is required
Sowing Method for Wheat Crop
- Broadcast Sowing: In broadcast sowing, wheat seeds are spread uniformly across the field either manually or using a spreader. The seeds are scattered over the soil surface without any specific row or line arrangement. This method is relatively simple and requires minimal equipment, but it may result in uneven seed distribution and lower yield compared to other methods.
- Kera and Pora Sowing: This sowing method involves manually placing the seeds in lines or furrows. Farmers create small holes or furrows in the soil using tools like a hand hoe or a stick and place the seeds at regular intervals along the lines. This method helps ensure better seed-to-soil contact and spacing, promoting uniform germination and growth.
- Rabi Drill Sowing: Rabi drill sowing is a method that involves using a specialized drill machine designed for sowing wheat. The drill creates rows or furrows in the soil and simultaneously drops the seeds at the desired depth and spacing. This method allows for precise and efficient sowing, ensuring uniform seed placement and optimum plant density.
- Zero Tillage: Zero tillage is a sowing method where the land is not prepared by conventional ploughing or tilling before sowing the seeds. Instead, specialized equipment like a zero tillage drill or happy seeder is used to directly sow the seeds into untilled soil. This method helps conserve moisture, reduces soil erosion, and promotes soil health.
- Bed Plantation: Bed plantation involves preparing raised beds or ridges before sowing the seeds. The beds are usually elevated and compacted to retain moisture and improve water drainage. This method is particularly useful in areas with poor soil drainage. Wheat seeds are then sown along the beds or ridges.
Varieties of Wheat
Wheat Varieties For Irrigated Areas
- Sahar- 2006
- Lasani- 2008 (Least effective with disease)
- FSD-2008(Saline soil) (Least effective with disease)
- Fakhre Bhakhar
- NN Gandam-1(most effective with disease)
- Galaxy-2013 (Most effective with disease)
- Bhakar star
Latest Varieties of Wheat Irrigated Areas
- Arooj 2022
- Durum 2021
- M.H 21
- Dilkash 21
- Subhani 21
Latest varieties of Wheat for south Punjab
Wheat Varieties For Arid Areas
- Chakwal -50
- Dharabi-2011(Least effective with disease)
- Markaz -2019
- M.A 21 (Latest)
Seed Rate of wheat
- Up to 30th Nov: 40-50 kg/ acre
- 1st to 15th Dec & later: 50-55 kg/acre
Note: In Faisalabad 2008 (up to 5 kg/ acre seed can be reduced) and for Lasani 2008 (up to 10kg/acre seed can be reduced) due to the production of more tillers
Main Source of wheat seed availability
- Punjab seed corporation
- Research Institute
- Private seed companies
- Authorized seed agencies/dealers
Wheat Seed Treatments
With (Thiophanate Methyl 2-2.51Kg of seed: Imidacloprid +Tebuconazole (Hombray: bayer) 2MI/ 1Kg of seed
Irrigations Requirements of Wheat Crop
The irrigation requirements for wheat can vary depending on various factors such as soil type, climatic conditions, and crop management practices
A. After Cotton, Maize, and Sugarcane Irrigation requirements for Wheat
- 1st irrigation: 20-25 days (Most Critical stage)
The first irrigation for wheat is typically carried out around 20-25 days after sowing, which is considered a critical stage. At this stage, the crop requires sufficient moisture for germination and early root development. Irrigation helps ensure the proper establishment of the crop.
- 2nd irrigation: 80-90 days (Spike formation stage)
The second irrigation is usually done around 80-90 days after sowing, during the spike formation stage. This stage is crucial for the development of the wheat plant’s reproductive structures, including the spikelets that will eventually form grains. Adequate soil moisture is necessary to support spike formation and optimize grain production.
- 3rd irrigation: 125-130 days (grain forming and filling stage)
The third irrigation takes place around 125-130 days after sowing, during the grain forming and filling stage. At this stage, the wheat plant is actively producing and filling grains. Sufficient water availability is critical for grain development and yield. Irrigation during this stage helps ensure proper grain filling and maximize crop productivity.
B. After Rice Irrigation requirements for Wheat
- 1st irrigation: 35-45 days
- 2nd irrigation: 80-90 days (Spike formation stage)
- 3rd irrigation: 125-130 days (grain forming and filling stage)
C. Late-sown wheat Irrigation requirements
- 1st irrigation: 25-30 days
- 2nd irrigation: 70-8- days (Spike formation stage)
- 3rd irrigation: 110-115 days (grain forming and filling stage)
Fertilizers Requirements of Wheat
1. For Irrigated Areas
- 2 bags DAP+ 1 bag Urea + 1 bag Potash at planting time
- 0.5 bag Urea in1st& 2nd irrigation
2. Rainfed Areas
- 1.5 bags DAP+ 1 bag Urea +1 bag Potash at planting
ZnSO433% Kg/acre and Boric acid 17% 2.5 kg/acre Note: Change according to your soil nutrient status
Major Weeds of wheat
- Phalaris minor (Dumbisitti): Phalaris minor, also known as canary grass or dumbi grass, is a troublesome weed in wheat fields. It competes with wheat for nutrients, sunlight, and water, and can significantly reduce crop yield if not effectively managed.
- Avena fatua (Jangli jai): Avena fatua, commonly called wild oats or jangli jai, is another common weed found in wheat fields. It can grow and spread rapidly, out-competing wheat plants and impacting yield. It is particularly challenging to control due to its ability to produce a large number of seeds.
- Chenopodium album (Bathu): Chenopodium album, also known as lambs quarters or bathu, is a broadleaf weed that can cause significant yield losses in wheat crops. It grows vigorously and competes for resources, affecting wheat growth and development.
- Chenopodium murale (Krund): Chenopodium murale, commonly referred to as nettleleaf goosefoot or krund, is another troublesome weed in wheat fields. It can quickly spread and reduce wheat yield by competing for nutrients, moisture, and light.
- Cirsium arvense (Leh): Cirsium arvense, also known as Canada thistle or leh, is a perennial weed that poses challenges in wheat fields. It has an extensive root system and can quickly establish dense patches, competing with wheat for resources and impacting crop yield.
Control of wheat Weeds
when reached ETL can be controlled by fenoxaprop-p-ethyle@ 400 ml/acre or clodinafop@ 100 gm/acre or pinozadin @330 ml/acre
When reached ETL can be controlled by various weedicides like Bromoxynil +MCPA @500 ml/acre or fluroxapyretc
Major Insects of wheat
1. Black Ants:
Chemical control specifically targeting black ants is generally not necessary unless they are associated with sap-sucking pests. In such cases, insecticides targeting the primary pests, such as aphids or scale insects, can be applied according to label instructions and recommended rates. It’s important to choose insecticides that are effective against the target pests while minimizing impacts on beneficial insects.
For termite control, soil-applied insecticides can be used. These insecticides are applied around the base of the plants or as a barrier treatment in the soil to create a protective zone. Consult with agricultural experts or pest control professionals to select appropriate insecticides and follow the recommended application rates and timing.
Insecticides specifically formulated for cutworm control can be used if significant infestations occur. Apply the insecticide to the soil around the base of the plants or as a foliar spray, targeting the feeding area of the larvae. Follow the instructions on the product label regarding rates, timing, and safety precautions.
Aphids are soft-bodied, practically translucent, sucking insects. Aphids have the ability to induce leaf yellowing and early mortality when they are present in large enough quantities. They release “honeydew” drips, a sugary liquid, which can leave small burn scars on the leaves. A significant and pervasive pest on cereal crops is aphids. They can do serious harm if they eat in large enough quantities. Additionally, the aforementioned species might serve as BYDV viral vectors. Aphids can be easily controlled by using the biological control method rather than the chemical method at that stage of the crop.) Numerous insecticides are available for controlling aphids in wheat. Select insecticides that are effective against aphids and have minimal impact on beneficial insects. Timing is crucial when applying insecticides for aphid control, as early detection and intervention are important to prevent population build-up.
It’s important to note that chemical control should be used judiciously and as part of an integrated pest management (IPM) approach. This approach includes regular monitoring, using cultural practices, and considering biological control methods to reduce reliance on chemical treatments. Always follow the instructions and safety precautions provided on the insecticide labels, and consult with local agricultural experts for specific recommendations based on your region and insect pest populations.
The major disease of wheat and Control
1. Rust Diseases
(Leaf Rust, Stem Rust, and Stripe Rust): Rust diseases are caused by fungal pathogens and are characterized by rust-coloured spores on leaves, stems, and spikes.
Leaf rust/Brown Rust of wheat
It is caused by the fungus Pucciniatriticina. Identifying symptoms are dusty, reddish-orange to reddish-brown fruiting bodies that appear on the leaf surface.
Stripe Rust/Yellow rust of Wheat
It is caused by the biotrophic fungus Puccinia striiformis. The main symptoms are the appearance of yellow streaks (pre-pustules), followed by small, bright yellow, elongated uredial pustules arranged in conspicuous rows on the leaves, leaf sheaths, glumes and awns
Stem rust/ Black Rust of Wheat
It is caused by the fungus Puccinia Graminis, Stem rust is characterized by reddish-brown, powdery, oblong pustules
To control rust diseases:
- Plant-resistant cultivars: Use wheat varieties that have been bred for resistance to specific rust pathogens.
- Fungicide application: Apply fungicides following recommended timing and rates to protect the crop from rust infections.
- Crop rotation: Practice crop rotation to break the disease cycle and reduce inoculum build-up.
- Wheat rust is a fungal disease that affects wheat, barley and rye stems, leaves and grains. In temperate zones, it is destructive on winter wheat because the pathogen overwinters. For controlling leaf rust, yellow rust and stem rust disease: Use of improved varieties having resistance against this disease
2. Fusarium Head Blight (Scab):
Fusarium head blight is caused by the fungus Fusarium spp. It affects wheat spikes, causing bleaching, shriveled grains, and mycotoxin contamination. Control measures include
- Plant-resistant cultivars: Use wheat varieties that show resistance or tolerance to Fusarium head blight.
- Fungicide application: Apply fungicides at flowering to suppress disease development.
- Crop rotation: Rotate wheat with non-host crops to reduce the risk of disease carryover.
3. Powdery Mildew:
Powdery mildew is caused by various fungal species and appears as a white, powdery growth on leaves. Control measures include
- Plant-resistant cultivars: Choose wheat varieties with resistance to powdery mildew.
- Fungicide application: Apply fungicides as needed based on disease severity and weather conditions.
- Proper plant spacing: Maintain adequate spacing between plants to improve air circulation and reduce humidity.
4. Septoria Tritici Blotch:
Septoria tritici blotch is caused by the fungus Zymoseptoria tritici and leads to small, necrotic lesions on leaves. Control measures include:
- Plant-resistant cultivars: Use wheat varieties that exhibit resistance or tolerance to Septoria tritici blotch.
- Fungicide application: Apply fungicides at appropriate timings to manage disease progression.
- Crop residue management: Remove and bury infected crop residues to minimize disease carryover.
5. Wheat Loose smut
It is caused by the fungus Ustilago tritici. Mild symptoms may be present prior to heading, including yellowish leaf streaks and stiff, dark green leaves
6. Kernel bunt of Wheat
It is caused by the fungus Tilletia Indica which infects grains at flowering, Karnal bunt is first visible at the soft-dough stage in the form of blackened areas surrounding the base of the grain and significantly reduces yield
For controlling loose smut and kernel bunt disease: seed treatment with recommended fungicide before sowing.
Harvesting & Storage of Wheat
- In Punjab, the harvesting period is April and May.
- Use hermetic bags for storage and storage moisture should not be more than 10%
Major recommendation for Wheat
- Sowing of wheat before November 20th should not be later than 10th Dec for good results
- Adoption of drill sowing
- Seed rate @ 40-50kg/acre (normal sowing) and 55-60 kg/acre (late sowing)
- Wheat seed rate when sowing in performed standing cotton crop is 55-60 kg/acre
- Use of quality seeds of recommended varieties
- No water shortage at tillering, booting and grain formation stage
- Use of recommended fertilizer doses
- Efficient weed control
- Adoption of mechanized harvesting/threshing
- Avoid harvest and post-harvest losses